mongodb: no reachable servers

  mongodb, question

After installing mongodb with brew in OS X environment
Import a json file according to the tutorial on official documents

mongoimport --db test --collection restaurants --drop --file primer-dataset.json

An error was reported during the process.

Failed: error connnecting to db server: no reachable servers

Seek a solution

Solutions already tried:
1.mongoimport --host= --port=27017 --db test --collection restaurants --drop --file primer-dataset.json
2.brew update && brew upgrade

1. Import the file after starting mongodb and report an error:

Failed: error processing document #9870: unexpected EOF
看上去像是数据文件损坏, vi打开看一下要导入的数据文件.

Are you sure your mongodb is activated?